This volume completes the three-volume collective scientific work "History of Hungary," which sets out the history of the Hungarian people from ancient times to the present day. The third volume is devoted to the events from 1918 to 1970 and is the first attempt in Soviet literature to scientifically generalize and systematically cover the socio-economic and political development of the country in the new era of human history, which opened with the victory of the Great October Socialist Revolution.